The present invention relates to a method and a device for agitating a liquid mixture, and is particularly useful for agitating a mixture of a serum with a dilutant.
One type of serial dilution machine is shown in U.S. Pat. No. 3,536,449, the disclosure of which is incorporated herein by reference. The principle of the method disclosed in said patent is illustrated in FIG. 1(a), FIG. 1(b) and FIG. 1(c) of the accompanying drawings. FIG. 1(a) is a plan view of a tray of the serial dilution machine. The tray 1 contains a plurality of rows of holes 2. The holes each have an inside diameter of about 6mm and a depth of about 10mm. FIG. 1(b) is a sectional view of a dilution rod (a rod for use in diluting). The dilution rod 5 has a hemispherical bowl 4 at an end of the rod. The bowl 4 has a diameter of about 3mm. FIG. 1(c) is a sectional view of the tray. A predetermined quantity of dilutant liquid 3 (a liquid for use in dilution of a serum) is contained in the holes 2 of the tray 1. The tray 1 is made of, for example, plastic, and the dilution rod is made of, for example, stainless steel. The size of the tray depends on the number of the holes.
Serial dilution is performed by using such a serial dilution machine as follows:
The dilution rod 5 is dipped in a serum to be diluted. A fixed quantity of the serum is retained in the bowl 4. The bowl 4 containing the serum is dipped in the hole 2 containing a dilutant liquid 3, and then the dilution rod is rotated to mix and dilute the serum with the dilutant liquid 3. The dilution rod having the diluted serum contained in the bowl is inserted in the next hole containing a dilutant liquid and then rotated as described above. By repeating such a procedure several times, serums diluted with a dilutant liquid can be obtained in each of the holes. In this case, if a quantity of a liquid contained in the bowl is equal to a quantity of a liquid contained in the hole, the serum will be diluted two, four, eight . . . times in turn.
In the conventional serum dilution machine, when many kinds of serums will simultaneously be diluted, many dilution rods must simultaneously be rotated as shown in U.S. Pat. No. 3,536,449. In such a machine, complex mechanisms and structures are required, and further, agitation of a liquid in the holes cannot be effected without the dilution rod.
Accordingly, an object of the present invention is to provide complete agitation of a liquid without the dilution rod, and complete mixing or diluting without rotation of the dilution rod.